Control and stabilization of a flight vehicle from a detected perturbation by tilt and rotation

ABSTRACT

A flight vehicle control and stabilization process detects and measures an orientation of a non-fixed portion relative to a fixed frame or portion of a flight vehicle, following a perturbation in the non-fixed portion from one or both of tilt and rotation thereof. A pilot or rider tilts or rotates the non-fixed portion, or both, to intentionally adjust the orientation and effect a change in the flight vehicle&#39;s direction. The flight vehicle control and stabilization process calculates a directional adjustment of the rest of the flight vehicle from this perturbation and induces the fixed portion to re-orient itself with the non-fixed portion to effect control and stability of the flight vehicle. The flight vehicle control and stabilization process also detects changes in speed and altitude, and includes stabilization components to adjust flight vehicle operation from unintentional payload movement on the non-fixed portion.

CROSS-REFERENCE TO RELATED PATENT APPLICATION(S)

This patent application claims priority to U.S. non-provisional patentapplication Ser. No. 15/091,566, filed on Apr. 5, 2016, which claimspriority to U.S. provisional application 62/143,610, filed on Apr. 6,2015, the contents of which are both incorporated in their entiretyherein. In accordance with 37 C.F.R. § 1.76, a claim of priority to the'566 application is included in an Application Data Sheet filedconcurrently herewith.

FIELD OF THE INVENTION

The present invention relates to control and stabilization of flightvehicles. Specifically, the present invention relates to detecting theorientation of a non-fixed portion of a flight vehicle relative to theother, fixed portion of the flight vehicle, and inducing the fixedportion to move in the direction of re-orientation with the non-fixedportion of the flying device following a detected perturbation in thenon-fixed portion.

BACKGROUND OF THE INVENTION

There are many existing prior art methods for control and stabilizationof aerial systems. Many modern flight vehicles, such as airplanes,employ various methods for controlling and stabilizing flightcharacteristics. Examples of these include flaps and rudders in wings,pilot-controlled rotors, gyroscopes, accelerometers, auto-stabilizationalgorithms, and automatic power-adjusted propulsion systems.

When effecting control of a flight vehicle, typically a user willperform an action such as rotating a steering column or pressing acontrol lever, causing the flight vehicle to turn in the directionspecified by the user. This is performed by adjusting a mechanicalaspect of the flight vehicle, such as for example a rudder. In somemodern flight systems, movement of the aircraft in the manner specifiedby the user is augmented by computer algorithms that adjust trajectoryin a certain manner. In such systems, the operator generally does notadjust their actual position or orientation, but adjusts a controlapparatus or device. In multi-rotor vertical take-off and landing (VTOL)flight vehicles, such as quadcopters, controlling the flight vehicle maybe performed by changing the rotor speed of one or some of the rotorsbased on operator input.

For flight vehicle stability, some systems rely on wings, while othersdepend on rotors and counter forces, such as the tail rotor of ahelicopter. Additionally, many modern flight systems use computerstabilization algorithms in combination with wings, orgyroscopes/accelerometers. The latter is especially common inmulti-rotor vertical take-off and landing (VTOL) style vehicles, tosense when the flight vehicle is no longer level, an adjust the speedsof certain rotors to level the flight system.

Additionally, some stabilization techniques use an outside frame ofreference, such as a camera that tracks various parts of the flightvehicle or connected devices or systems, such as an object hanging fromthe flying device, or resting on top of the flying device. When thesetracked points of the flight vehicle or connected devices or systemsmove in a certain way, as specified and recognized by the controlalgorithms, the control algorithms direct the flight vehicle to takesome action (such as increase rotor speed to a particular rotor), inorder to keep the flight vehicle stable.

BRIEF SUMMARY OF THE INVENTION

It is therefore one objective of the present invention to provide asystem and method for control of a flight vehicle having a non-fixedcomponent coupled to a fixed component and upon which a load istransportable. It is another objective of the present invention toprovide a system and method for stabilization of such a flight vehicle.

It is another objective of the present invention to provide a system andmethod for control and stabilization of a manned flight vehicle that ismaneuverable by movement of a pilot or rider stationed on the non-fixedcomponent. It is yet another objective of the present invention toprovide a system and method that allows the pilot or rider to maneuverthe flight vehicle by tilting and/or rotating themselves on thenon-fixed component.

The present invention comprises one or more systems and methods thatinclude a flight vehicle control and stabilization process. A flightvehicle incorporating the present invention may be comprised of anon-fixed portion, such as a platform upon which a rider and/or payloadis placed, that is coupled to a fixed portion or frame. The flightvehicle may be any kind of flying device, including (but in no waylimited to) a multi-rotor copter such as a helicopter, an airplane, anda hover-bike or hovercraft. As noted above, the flight vehicle may bepiloted or otherwise occupied by a rider. The flight vehicle may also beunmanned or remotely-piloted. The flight vehicle control andstabilization process may further be implemented in whole or in part ina hardware component, such as an embedded system or dongle. Such ahardware component is removable and/or programmable for various missionsand for many types and configurations of flight vehicles.

The flight vehicle control and stabilization process includes detectingand measuring both an orientation of the non-fixed portion of the flyingdevice relative to the fixed portion, and a degree of perturbation froman initial planar position of the non-fixed portion. The flight vehiclecontrol and stabilization process also includes inducing motion in thefixed portion of the flight vehicle in response to the orientation ofthe non-fixed portion and the detected perturbation to move the fixedportion of the flight vehicle in a direction of re-orientation with thenon-fixed portion where it may re-orient the fixed portion to match orsubstantially match that of the non-fixed portion of the flight vehicle.

Control and stabilization of a flight vehicle is further accomplished bydetecting at least one of a tilt of the non-fixed portion in one or moredirections transverse to a planar axis thereof, and rotation in one ormore directions along the planar axis of the non-fixed portion. Tiltingand/or rotation of the non-fixed portion by a rider or payload shiftproduces the perturbation from a prior planar position. The presentinvention measures the degree of perturbation and calculates adirectional adjustment for the fixed portion of the flight vehiclefollowing the tilt and/or rotation, and moves the fixed portion in thedirection of re-orientation with the non-fixed portion in response tothe directional adjustment, so that an orientation of the fixed portionmatches or substantially matches an orientation indicated by the newplanar position of the non-fixed portion relative to the fixed portion.The present invention may also calculate rates of change in the tilt androtation of the non-fixed portion, and conduct the re-orientation of thefixed portion at a specific angular velocity reflective of thosecalculations.

The flight vehicle control and stabilization process of the presentinvention is also configured to determine, from the degree ofperturbation, whether one or more of the tilt and the rotation exceedspreset threshold values. The fixed portion may be re-oriented tostabilize the flight vehicle to compensate for a degree of perturbationresulting where the one or more of the tilt and rotation exceed thepreset threshold values. Regardless, the flight vehicle control andstabilization process of the present invention minimizes horizontalforces acting on certain regions of the flight vehicle, and focuses onthe region where a load may be placed on or otherwise connected to thenon-fixed portion, relative to the planar axis of the non-fixed portion.

After a perturbation is detected, the fixed portion of the flightvehicle responds to the calculated directional adjustment to move in thedirection of re-orientation with the non-fixed portion, and may match orsubstantially match a planar position relative to the non-fixed portion.The fixed portion may therefore be induced to reach the same position asthe non-fixed portion, or it may move in towards full reorientation butnot fully reach the same position, thereby stopping short of a fullre-orientation. The process may stop adjusting the fixed portion once itreaches a certain level of proximity to the desired position relative tothe non-fixed portion, or if it reaches a certain position relative theground. In this manner, the process may include components thatanticipate subsequent perturbations from tilt and/or rotation of thenon-fixed portion.

Inducing the re-orientation of the fixed portion of the flight vehiclemay be accomplished by one or more computer algorithms that adjustengines or thrusters based on the measured degree of perturbation,change in position, of the non-fixed portion relative to the rest of theflight vehicle. It may also be accomplished by mechanical means, such asfor example springs or other mechanical apparatuses, that induce thefixed portion of the flight vehicle to move in the direction ofre-orientation relative to the non-fixed portion. These computeralgorithms and mechanical means may operate in tandem, or separately.

Other objects, embodiments, features and advantages of the presentinvention will become apparent from the following description of theembodiments, taken together with the accompanying drawings, whichillustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several embodiments of theinvention and together with the description, serve to explain theprinciples of the invention.

FIG. 1 is a flow chart of elements in a process for control andstabilization of a flight vehicle according to the present invention;

FIG. 2 is a perspective view of an exemplary flight vehicle according toone aspect of the present invention;

FIG. 3A is a cross-sectional view of the exemplary flight vehicle ofFIG. 2;

FIG. 3B is another cross-sectional view of the exemplary flight vehicleof FIG. 2 showing tilting of a non-fixed portion of the flight vehicle;

FIG. 3C is another cross-sectional view of the exemplary flight vehicleof FIG. 2 showing tilting of a fixed portion in response to a tilt inthe non-fixed portion of the flight vehicle;

FIG. 4 is a perspective view of another exemplary flight vehicle inwhich the present invention is embodied;

FIG. 5 is a perspective view of yet another exemplary flight vehicle inwhich the present invention is embodied; and

FIG. 6 is a perspective view of still another exemplary flight vehiclein which the present invention is embodied.

DETAILED DESCRIPTION OF THE INVENTION

In the following description of the present invention reference is madeto the exemplary embodiments illustrating the principles of the presentinvention and how it is practiced. Other embodiments will be utilized topractice the present invention and structural and functional changeswill be made thereto without departing from the scope of the presentinvention.

The present invention is a flight vehicle control and stabilizationprocess 100, for operation of a flight vehicle 200 that is comprised ofa non-fixed portion 210 coupled to a fixed portion or frame 220. Theflight vehicle control and stabilization process 100 is performed withinone or more systems and/or methods as described further herein.

FIG. 1 is a flow chart illustrating various functions of the presentinvention, according to one embodiment thereof. In this embodiment, acontrol and stabilization algorithm for flight vehicle operation isinitialized at step 110. This may occur for example where a flightvehicle is first powered on. The process 100 begins by analyzing aplanar position of a non-fixed portion 210 of a flight vehicle 200 atstep 120, by detecting whether a perturbation from an initial planarposition of the non-fixed portion has occurred. The process 100identifies and measures a degree of such perturbation relative to thefixed frame 220, and then compares, at step 130, the degree ofperturbation with maximum and minimum threshold values for either orboth of tilt or rotation. Where a degree of perturbation does not exceeda minimum threshold value 134, the process 100 may return a no or nullvalue that indicates a “yes” at step 135 to proceed under current/normalconditions. The result, at step 136, is the flight vehicle 200 isallowed to continue operation in its current state.

The comparison at step 130 also checks for whether the degree ofperturbation exceeds a maximum threshold value at step 132. Where adegree of perturbation is within the maximum and minimum thresholdvalues, the process 100 may return a yes value 133, and continues bycalculating a directional adjustment of the fixed frame 220 in responseto one or both of the tilt or rotation at step 140. This calculation ofthe directional adjustment at step 140 may further include determining anew planar position of the non-fixed portion relative to the fixedportion, and calculating an angular velocity for a re-orientation of thefixed portion in response to the directional adjustment from a rate ofchange in the tilt in one or more directions transverse to the planaraxis of the non-fixed portion, and a rate of change in the rotation inone or more directions along the planar axis. The calculation of thedirectional adjustment may also include a comparison of the planarposition, following perturbation from tilt and/or rotation, with aground, level, or horizon, or a substantially horizontal planar positionof the non-fixed portion 210.

A degree of perturbation may be comprised of one or multiple components,such that the degree may have both a direction and a magnitude, and mayinclude a specific angular differential. The flight vehicle control andstabilization process 100 may therefore identify a degree ofperturbation by measuring one or both of a directional change resultingfrom the perturbation and a magnitude of such a directional change. Manydifferent parameters may represent such a directional change andmagnitude thereof, such as for example an angular differential from aplanar position.

For example, the flight vehicle control and stabilization process 100may sense and measure a degree of tilt (such as in 12° or 6° from aprior planar position by way of additional example). When the tilt anglebetween the non-fixed portion 210 and the fixed portion 220 isdetermined to be non-zero, the flight vehicle control and stabilizationprocess 100 calculates the directional adjustment and communicatesappropriate signals to the engines powering the flight vehicle 200 tofire in such a way to move the fixed portion in the direction ofre-orientation with the non-fixed portion, and may re-orient the fixedportion 220 to return that angle back to zero.

In another embodiment, one or more sensors 240 measure a linear distancebetween those sensors and a paired “sister” sensor on the fixed portion220. When that distance increases, the flight vehicle control andstabilization process 100 calculates the directional adjustment andcommunicates appropriate signals to the engines powering the flightvehicle 200 to adjust in a manner that re-orients the fixed portion 220to return the linear distance back to a value prior to the perturbation.

At step 150, the flight vehicle control and stabilization process 100induces the movement in the direction of re-orientation of the fixedframe 220, and may match or substantially match the orientation of thenew planar position of the non-fixed portion 210 following theperturbation from tilt and/or rotation. It is to be understand that thecalculation of the directional adjustment at step 140 may indicate thatrealization of the inducing a re-orientation would result in a positionof the fixed portion that is almost the same as that of the non-fixedportion, rather than exactly the same. In other words, the calculationof the directional adjustment may take into account one or more forcesacting on the non-fixed portion from a re-orientation of the fixedportion, and may anticipate an intended direction from the perturbationof the planar position of the non-fixed portion from tilt and/orrotation thereof and induce a movement of the fixed portion in thedirection of re-orientation with the non-fixed portion.

Where the comparison step determines that the degree of perturbation isnot within the maximum and threshold values (in conjunction with step134), the process 100 concludes that the degree of perturbation exceedsa maximum threshold value and returns a no or null state 137. Thisinitializes an emergency stabilization at step 180, and the processcalculates an appropriate responsive adjustment to the degree ofperturbation.

At step 160, the flight vehicle control and stabilization process 100continues by adjusting one or more propulsion forces acting on theflight vehicle 200 to reach a new altitude and/or a new speed inresponse to the perturbation of the planar position of the non-fixedportion from tilt and/or rotation thereof. Step 160 is performed toensure that one or both of an altitude or speed is maintained for theflight vehicle 200 following a re-orientation of the fixed frame 220. Atstep 160, an adjustment of the propulsion forces may occur because theflight vehicle 200 is induced to move horizontally in the direction ofthe tilt, when the non-fixed portion is induced to tilt. The horizontalspeed of the flight vehicle 200 would therefore increase, and the moretilt applied to the non-fixed portion, the faster, horizontally, theflight vehicle 200 may accelerate.

In an initial position, and before the flight vehicle 200 is induced totilt, thrusters are normally facing straight down, so that all of theforce from them is keeping the flight vehicle at one position, However,when the non-fixed portion 210 tilts, and the fixed frame 220 is inducedto tilt itself to re-adjust, the new direction of the thrusters is nolonger vertically down, but now at an angle. If the thrust remained thesame, the flight vehicle 200 would lose altitude, as not all of theforce from the thrusters would be in the vertical, Y-axis direction.However, because the thrusters are now tilted, a portion of that thrustwould be in the horizontal, X-axis direction. The thrust of the enginesacting as propulsion forces must therefore increase when the fixedportion 220 is titled to re-orient with the non-fixed portion 210, inorder for the flight vehicle 200 to maintain a constant altitude.Additionally, the thrust increases as a function of the angle of tilt ofthe overall, re-orientated flight vehicle 200.

It is to be noted that the altitude and speed of the flight vehicle 200may also be controlled from either some perturbation of the planarposition of the non-fixed portion 210, or by another means of indicatingthat a change in altitude or speed is desired. Many examples of this arecontemplated in the present invention. In one such example, the flightvehicle control and stabilization process 100 may detect a unique tap,or set of taps, for example by one or both feet of a pilot or rider onthe non-fixed portion 210, and may further identify a unique or specifictiming between taps (or a duration of pressure or non-pressure of tapsduring a tap or tap sequence) to ascertain intended instructions to theflight vehicle from the pilot or rider. These instructions may be for avariety of flight characteristics, such as altitude adjustment,pre-programmed navigational sequences, or a ‘return to launch site’command”. In another example, such instructions may be provided by arapid, or quick, jolt on a part (back, front, etc.) of the non-fixedportion, followed by a subsequent rapid or quick jolt on another part ofthe non-fixed portion. In such an example, the amount of the increase inaltitude is a function of the timing and spacing of the locations ofthese rapid or quick jolts. Regardless, it is to be understood that manyways of indicating a desired change in altitude or speed are possible.

The calculation of the directional adjustment at step 140 may furthercomprise, as noted above, a stabilization step. The threshold tilt androtation values compared at step 130 represent minimum threshold values,below which no directional adjustment is calculated. Above thosethreshold values, the flight vehicle control and stabilization process100 performs the various mathematical manipulations and functionsdescribed further herein to determine the amount of re-orientationneeded in the fixed portion 220 of the flight vehicle 200.

The comparison step 130 may also include, however, a comparison withmaximum tilt and rotation threshold values, above which a stabilizationportion of the process 100 is initiated to correct an error state. Suchan error state may occur, for example, where a payload carried bynon-fixed portion 210 overturns, causing a large change in the center ofthe mass of the non-fixed portion, and/or a rapid movement of thenon-fixed portion 210 beyond pre-specified levels. It is therefore to beunderstood that different maximum and minimum values for these thresholdvalues may be set, for different missions undertaken by the flightvehicle 200, and depending on the type of payload to be transported.

Step 140 may therefore include such a stabilization portion, bycalculating a directional adjustment to compensate for a degree ofperturbation resulting from one or more of tilt and rotation thatexceeds maximum preset threshold values. Additionally, step 150 mayinclude inducing a re-orientation of the fixed portion to stabilize theflight vehicle 100.

The flight vehicle control and stabilization process 100 also includes afeedback loop that continually analyzes whether tilt or rotation isactuated on the non-fixed portion 210 to detect additional perturbationsin a planar position. At step 170 this feedback loop determines whetheran additional perturbation has occurred, and if yes at step 172, returnsto step 130 for a comparison of the degree of perturbation againstthreshold tilt and rotation values. If no, at step 174, the process 100takes no action and allows the flight vehicle 200 to continue withoperation in a current state at step 136.

As suggested above, the present invention contemplates that are-orientation of the fixed portion 220 may match, or substantiallymatch, an orientation of the non-fixed portion 210. Therefore, thepresent invention may not induce the fixed portion 220 to re-orientitself to the precise, post-perturbation angular position of thenon-fixed portion, and therefore may not effect a “full” re-orientation.In such a situation, the present invention may anticipate an intendedsubsequent direction from an additional perturbation of the planarposition of the non-fixed portion 210. The process 100 may thereforestop or slow the adjustment of the fixed portion 220 once it reaches acertain level of proximity to the desired position relative to thenon-fixed portion 210, or if it reaches a certain position relative theground. The process 100 may include components that anticipatesubsequent perturbations from tilt and/or rotation of the non-fixedportion 210. These components may be responsive to various parameters,such as operating conditions, mission-specific characteristics, payloadrules, and other factors.

The flight vehicle control and stabilization process 100 may beperformed within a specific computing environment, and the systems andmethods embodying the present invention includes a plurality of stepsthat are carried out by plurality of data processing modules. Thecomputing environment includes one or more processors and a plurality ofsoftware and hardware components for further performing the flightvehicle control and stabilization process 100. The one or moreprocessors and plurality of software and hardware components areconfigured to execute program instructions or routines to perform thefunctions described herein, and embodied by the plurality of dataprocessing modules.

FIGS. 2-6 show various embodiments of flight vehicles 200 thatincorporate the flight vehicle control and stabilization process 100.Flight vehicles 200, for example as in the perspective view of FIG. 2and the cross-sectional views of FIG. 3A-3C, include a non-fixed portion210 as noted above, coupled to a fixed portion or frame 220. The fixedportion or frame 220 may include one or more rotors 222, where theflight vehicle 200 is a multi-rotor copter, such as for example aquadcopter. Regardless of the configuration, the non-fixed portion 210is at least partially mobile, and capable of motion relative to thefixed portion 220.

The non-fixed portion 210 may include a platform 212 that is coupled tothe fixed portion 220 with one or more tensile coupling mechanisms 230.The platform 212 is capable of supporting a pilot or rider 214, standingor sitting on thereon, or an inanimate payload 216. In the flightvehicles 200 shown in FIG. 2 and FIG. 3A-3C, the platform 212 hangsbelow or slightly below the fixed portion 220, whereas in otherembodiments (such as for example in FIG. 4), the platform 212 comprisingat least part of the non-fixed portion may be positioned level with, oron top of, the fixed frame 220. Regardless, it is to be understood thatthe tensile coupling mechanisms 230 enable the non-fixed portion 210 tomove, in either or both of a rotatable fashion or a tilting fashion,relative to the fixed portion 220, so as to deviate from a planarposition of the non-fixed portion 210.

One or both of the non-fixed portion 210 and the fixed portion 220 ofthe flight vehicle 200 may include sensors 230. These sensor 230 detectand identify tilting and/or rotation of the non-fixed portion 210relative to the rest of the flight vehicle 200. Sensors 230 may also bepart of the tensile coupling mechanisms 240, or responsive to movementtherein such as vibrations, for the purpose of detecting and identifyinga perturbation of the planar position of the non-fixed portion 210. Datafrom the sensors 230 may be provided to one or more processingcomponents that measure the degree of perturbation and determine adirectional adjustment therefrom.

FIG. 4 is a perspective view of one embodiment of a flight vehicle 200in which the present invention is incorporated. In this embodiment, theflight vehicle 200 is a multi-rotor hovercraft, and the non-fixedportion 210 is on top of, or flush with, a horizontal plane of the fixedportion 220. The non-fixed portion 210 includes a platform 212 uponwhich an inanimate payload 216 is placed. Such a flight vehicle 200 maybe used for unmanned package deliveries.

FIG. 5 is a perspective view of a further embodiment of a flight vehicle200 in which the present invention is incorporated. In this embodiment,the flight vehicle 200 is a hovercraft in the form of a hover-bike,where the rider 214 is seated on a motorcycle or bicycle-style seat.This seat forms the non-fixed portion 210, which is coupled to the fixedframe 220 by the tensile coupling mechanisms 230. Movement of the rider214 on the seated non-fixed portion 210, either by tilting orturning/rotating, causes the fixed portion 220 to re-orient itselfaccordingly. FIG. 6 is a view of a further embodiment of a flightvehicle 200 in which the present invention is incorporated. In thisembodiment, the flight vehicle 200 is formed as a body suit worn by thepilot or rider 214. The body suit may incorporate both a non-fixedportions 210 and a fixed portion 220, and one or sensors 240 maytherefore be worn on the body suit itself.

Regardless of the type or configuration of tensile coupling mechanism230 or sensor 240, and regardless of the flight vehicle 200configuration, the present invention is configured to calculate thedirectional adjustment and induce a re-orientation in the fixed portion220 where a perturbation from a planar position occurs in the non-fixedportion 210. Such a perturbation may be effected by a rider or pilot 214for the purpose of controlling the flight vehicle 200, or may resultfrom a shift in a payload 216, or both.

The pilot 214 is able to induce a re-orientation of the fixed portion220 by tilting or rotating the non-fixed portion 210, from moving his orher body in the desired direction. When positioned on the platform 212(standing, sitting, or reclined/prone in some manner), and the pilot 214moves the body forward, backward, or angularly in one or more directionstransverse to a planar axis of the non-fixed portion 210, this actionalters the planar position of the platform 212 by tilting. Similarly, ifthe pilot moves the body to the left or to the right along the planaraxis, this action also alters the planar position of the platform 212 byrotation. Together or separate, these actions cause a perturbation inthe planar position of the non-fixed portion 210. The flight vehiclecontrol and stabilization process 100 detects and measures thisperturbation, and calculates the directional adjustment according to thedegree of perturbation.

The flight vehicle control and stabilization process 100 is implementedin a flight vehicle 200 as in, for example, the embodiments showing inFIGS. 2, 3A-3C, 4, 5 and 6. The present invention is, in one aspectthereof, a method of detecting or sensing, the orientation of thenon-fixed portion 210 of the flight vehicle 200 relative to the fixedframe 220. When the orientation of the non-fixed portion 210 of theflight vehicle 200 changes, relative to the other, fixed portion 220,the orientation of the fixed frame 220 is induced to move in thedirection of re-orientation with the non-fixed portion, and may matchthe orientation of the non-fixed portion 210 by moving in a certainmanner and according to the mathematical calculations and functionsdescribed herein.

It is to be understood that both tilt and rotation of the non-fixedportion may effect directional changes in the non-fixed portion 210.Rotational changes of the non-fixed portion 210 relative to the fixedframe 220, about the vertical axis of the non-fixed portion 210, whichis the axis perpendicular to the plane of the non-fixed portion 210, maytherefore also be incorporated. In this case, the fixed frame 220 wouldthen be induced to rotate, to move rotationally in the direction ofre-orientation with the non-fixed portion, and may match the rotation ofthe non-fixed portion 210, in a similar manner to the way it adjustsitself to the orientation of the non-fixed portion 210 following tiltingthereof.

In determining a directional adjustment in the flight vehicle controland stabilization process 100, threshold values that represent themaximum levels that the non-fixed portion 210 is permitted to tilt androtate may be utilized. When a maximum threshold tilt or rotation isexceeded, a stabilization protocol may be initiated, as this isindicative of an emergency condition. Similarly, threshold values thatrepresent a minimum that the non-fixed portion 210 is permitted to tiltand rotate without initiating a directional adjustment calculation mayalso be utilized. Tilting and rotating below this minimum thresholdvalue may be deemed as normal operational fluctuations in planarposition, and the flight vehicle 200 is permitted to continue in itscurrent flight state without adjustment. Regardless, it is to beunderstood that these maximum and minimum threshold values may be presetconditions that depend on the type of craft, configuration of the craft,flight conditions, type of mission, type of payload, and whether theflight vehicle 200 is manned or unmanned. The maximum and minimumthreshold values may also be automatically or manually set, and may bechanged, for example as conditions change during a flight or mission.

The flight vehicle control and stabilization process 100 may operate ina continuous manner as a feedback loop, so as to check for aperturbation at for example, a rate of many times per second. If it isfound that the orientation of the non-fixed portion 210 relative to thefixed portion 220 has changed to a degree that is within these thresholdvalues, the present invention directs one or more signals to the fixedportion to move in the direction of re-orientation relative to thenon-fixed portion 210. A re-orientation from a calculated directionaladjustment may be accomplished by, by way of example, changing theamount of power to various rotors on the flight vehicle 200, or changingthe angle of a vertical jet on the flight vehicle, or it may beaccomplished by another means. It is to be noted that different types offlight vehicles 200 and configurations thereof may include differentsystems and methods of powering them during flight, and therefore themeans for accomplishing the re-orientation may be dependent on theflight vehicle 200 itself. Regardless, the feedback loop of detectingand the inducement of movement continues as long as the flight vehicle200 is powered on or otherwise in a flight mode.

One way in which the present invention provides control and stability toa flight vehicle 200 is by minimizing the effective horizontal force,and its derivatives, relative to the plane of the non-fixed portion 210(henceforth referred to as the horizontal force). Specifically, if thenon-fixed portion 210 that is initially aligned with the rest of theflight vehicle 200 tilts by changing its transverse orientation, but thefixed portion 220 is still being propelled in the same direction it wasbefore tilting movement, there will be horizontal forces relative to theplane of the non-fixed portion 210 on any load resting on or otherwiseconnected thereto.

This causes instability, as the sum of the forces acting on the flightvehicle 200 by the resulting horizontal force and the propulsion forceof the fixed portion 220 results in a torque that will cause the flightvehicle 200 to tip to one side. If no adjustments are made, this tippingwill continue, and the flight vehicle 200 will overturn.

However, if the fixed portion 220 is induced to change its orientationand move in the direction of re-orientation with the non-fixed portion210 to the extent that it may match the orientation of the non-fixedportion 210, then the sum of forces acting on the flight vehicle 200will be such that there is little or no torque, and the flight vehicle200 will become stable as both the non-fixed portion 210 and the fixedportion 220 will stay at the angle θ to which the non-fixed portion 210was tilted.

This is therefore one way that the present invention effects control ofa flight vehicle 200—when the process 100 detects that the non-fixedportion 210 has tilted by an angle θ 250 as in for example FIG. 3B, thefixed portion 220 moves in the direction of re-orientation with thenon-fixed portion 210, to the extent that it may match the orientationof the non-fixed portion 210, to yield an overall force and manipulatethe flight vehicle 200 in that direction. In this manner, the flightvehicle 200 is stabilized following the perturbation, and directionalcontrol is achieved by orienting the fixed portion 220 in response tothe tilt angle θ 250 of the non-fixed portion 210, such that theresulting tilt angle 260 of the fixed portion 220 may be similar indegree and direction.

In this example, as some of the vertical force that was maintaining thealtitude of the flight vehicle 200 has now been re-directed to propel itlaterally, the overall sum of the propulsion force must be increased inorder to maintain the same elevation as before the tilt. If thenon-fixed portion 210 is then tilted back in the opposing direction atan angle θ′, the fixed portion 220 will again reorient itself. When ithas reached a satisfactory re-orientation relative to the non-fixedportion 210, another force in that opposing direction will be obtained.This allows the pilot 214 to control the direction of the flight vehicle200 by intentionally tilting and/or rotating the non-fixed portion 210in the direction that the pilot 214 wishes to travel.

It is therefore to be understood that the tensile coupling mechanisms230 must allow for adequate movement of the non-fixed portion 210relative to the other portion of the flight vehicle 200. In one aspectof a flight vehicle 200 incorporating the present invention, thenon-fixed portion 210 must be able to transversely tilt, in any or allof pitch, roll, and yaw dimensions, so that if a load is on thenon-fixed portion 210, and that load tilts or otherwise changes itscenter of mass (for example by falling or shifting), the non-fixedportion 210 must have sufficient mobility enough to tilt or rotateaccordingly. As suggested above, tilting threshold value may bespecified, so that if the non-fixed portion 210 tilts too far, analternative or additional stabilization method may be enacted to betterstabilize the flight vehicle 200. The non-fixed portion 210 may also beable to rotate about the planar axis of the non-fixed portion 210 of theflying device 200.

The flight vehicle control and stabilization process 100 also determinesthe manner, which may be described as the angular velocity, in which thefixed portion 220 moves while moving in the direction of re-orientationwith the non-fixed portion 210. This angular velocity is a function ofthe rate of change detected in one or both of the tilt and rotationmovements imparted to the non-fixed portion 210. The fixed portion 220may therefore move with varying levels of angular velocity, depending onone or both of the relative angle and the rate of change of the relativeangle between the non-fixed portion 210 and the fixed portion 220. Itmay move quickly when there is a large differential, to achievestability, and it may move slowly when there is a small differential toallow for a smooth ride. Additionally, the angular velocity of the fixedportion 220 may change during the process of re-orientation.

The angular velocity of the re-orientation of the fixed portion 220 ofthe flight vehicle 200 may be described as a non-linear or linearfunction, or a set of non-linear and linear functions, of the degree,rate of change, and change of rate of change of the perturbation, aswell as other parameters related to potentially the load, weather, typeof flying, etc., where the manner in which the fixed portion moves inthe direction of re-orientation with the non-fixed portion is designedto optimize stability and control, which may be different in variousembodiments of the invention. It may be described as:

ω=f(φ,φ′,φ″,φ′″,φ″″,K,g(φ,φ′,φ″,φ′″,φ″″,L))

Where φ represents the degree of perturbation, φ′, φ″, φ′″, φ″″ are thefirst, second, third and fourth derivatives of p, K and L are sets ofconstants with the appropriate dimensions, and f and g are functions orsets of functions, and may be differential equations and may involveintegrands, that may include exponential, trigonometric and non-realterms, in addition to standard mathematical operations of addition,subtraction, division, multiplication.

In the case where there are both tilting and rotational differentials atthe same time, the directional adjustment of the fixed portion 220relative to the non-fixed portion 210 may treat each of the tilt androtational re-orientations as linearly independent movements, or maylink them so as to process the movements together to calculate amulti-variate angular velocity. Regardless, it is to be understood thatthe present invention may analyze a response angular velocity from tiltand rotational perturbations in any manner designed to minimize thechange of the center of mass as re-orientation of the flight vehicle 200occurs.

Tensile coupling mechanisms 230 comprise a means for coupling thenon-fixed portion 210 to the fixed portion 220, and may include anydevice or mechanism that attaches the non-fixed portion 210 to the restof the flight vehicle 200, while still remaining flexible or elastic soas to enable the non-fixed portion 210 to tilt and/or rotate in anydirection relative to the rest of the flight vehicle 200. Tensilecoupling mechanisms 230 may have one or more mechanical components thatact on the rest of the flight vehicle 200 to “pull” it in the directionof re-orientation with the non-fixed portion 210 of the flying device200, relative to the tilt or rotation.

Examples of tensile coupling mechanisms 230 include, but are not limitedto, metal springs with rubber damping pads, hydraulic couplingmechanisms that allow motion while providing a dampening property,magnets that hold the non-fixed portion of the flight device ‘in place’with the rest of the flight device, but such that the non-fixed portion210 does not actually touch the rest of the flight vehicle 200, andother mechanisms that hold the non-fixed portion 210 ‘in place’ whilenot actually touching the rest of the flying vehicle 200, such ashinges. Tensile coupling mechanisms 230 may be made only of rubber, ormay include chains or cables such that the platform 212 of the non-fixedportion 210 hangs from them.

It is to be understood that the means for coupling the non-fixed portion210 with the rest of the flight vehicle 200 is not to be limited to anyone mechanism in a system or method described herein. It is to befurther understood, however, that the non-fixed portion 210 must becoupled to the rest of the flight vehicle 200 in some manner, such as byphysically touching or otherwise, while still providing mobility so thatthe non-fixed portion 210 may tilt and/or rotate, or be tilted orrotated, relative to the fixed portion 220.

As noted above, one or more springs may comprise the tensile couplingmechanisms 230. Where one or more springs couple the non-fixed portion210 with the rest of the flight vehicle, the springs may measure orregister the degree to which the non-fixed portion 210 has tilted, bythe stretch of the spring. The stretched spring exerts a greater forceon attachments on the end opposite the tilt or rotation. Given theseforces, the spring(s) would exert a force on, or pull, the rest of theflight vehicle 200 in the direction of re-orientation with the non-fixedportion 210. Thus, the rest of the flight vehicle 200 moves in thedirection of re-orientation with the non-fixed portion 210.

In one embodiment of the flight vehicle 200 within which the flightvehicle control and stabilization process 100 of the present inventionis incorporated, a perturbation of the non-fixed portion 210 from aplanar position thereof is detected, or measured, by one or more sensors240 that are positioned on one or both of the non-fixed portion 210 orthe fixed frame 220. Sensors 240 comprise a means for detecting such aperturbation and/or measuring a degree thereof, and may include anydevice that recognizes the orientation or location, or change oforientation or location, of the non-fixed portion 210 relative to therest of the flight vehicle 200.

Examples of sensors 240 include, but are not limited to, electromagneticwave-based measurement devices (within the visible spectrum orotherwise), sonar-based devices, and magnets. Sensors 240 may alsoinclude mechanical components, such as for example where a compressionof a spring is measured, or where certain vibrations in the tensilecoupling mechanisms 230 are detected. Sensors 240 may be placed inmultiple locations on either of the non-fixed portion 210 or the fixedportion 220 of the flight vehicle 200. The present inventioncontemplates that at least one sensor 240 is utilized to perform thedetecting and/or measuring aspects of the flight vehicle control andstabilization process 100.

Sensors 240 may further measure the relative angle of the non-fixedportion 210 and the fixed portion 220 of the flight vehicle 200 to anoutside frame, to a gravitational direction, or to ground. In oneembodiment, these sensors 240 may comprise gyroscopes and/oraccelerometers, in one or both of the non-fixed portion 210 and thefixed portion 220 of the flight vehicle 200, for measuring theirrespective orientations and enable calculations of the difference inorientation. Sensors 240 may also include relative distance measuringdevices that measure the distance and difference in distance betweenvarious parts of the non-fixed portion 210 and the fixed portion 220,enabling a determination of the relative orientation between thenon-fixed portion 210 and the fixed portion 220 of the flight vehicle200.

It is to be understood that the means for detecting a perturbation,and/or measuring a degree thereof, is not to be limited to any one typeof sensing component in a system or method described herein. It is to befurther understood, however, that the sensing component must beconfigured to determine the relative location or orientation, or changein location or orientation, in planar position resulting from a tiltand/or rotation of the non-fixed portion 210 relative to the fixed frame220 of the flight vehicle 200. Any known device that accomplishes thisobjective is contemplated to be within the scope of the presentinvention.

As noted above, the flight vehicle 200 may be configured to carry apayload 216 on the platform 212 of the non-fixed portion 210. A payload216 may include inanimate objects such as a package or other item fordelivery, for example where the flight vehicle 200 is an unmanned aerialvehicle such as drone configured to delivery to a customer. A payload216 may also include objects such as a camera or other imaging system,such as where the flight vehicle 200 is configured for photography.Other objects that may comprise a payload include weapons, weaponssystems, satellites, other craft, or any other items that can betransported or used in flight.

A flight vehicle 200 incorporating the present invention may be any kindof manned, unmanned, or remotely-piloted aerial system. As noted above,flight vehicles 200 may include, but are not limited to, multi-rotorcopters such as helicopters, quadcopters (as shown for example in FIG.2, and 3A-C), and other multi-rotor aerial systems such as that shown inFIG. 4, as well as airplanes, hover-bikes (such as that shown in FIG.5), an apparatus worn as a body suit (such as that shown in FIG. 6) orother hovercraft. Many configurations of such flight vehicles 200 arecontemplated, and it is to be understood that the present inventionshall in no way be limited by any specific configuration or type offlight vehicle 200 described herein.

This present invention also contemplates, as noted throughout, one ormore algorithms that act to stabilize a flight vehicle 200 based on thetilting and/or rotating of the non-fixed portion 210, regardless ofwhether the tilt or rotation was intentional or unintentional.Stabilization of the flight vehicle 200 looks to minimize (i.e.approaching zero) horizontal force on any object positioned on orotherwise connected with the non-fixed portion 210. For example, avertical height of the non-fixed portion 210, or other aspects of theapplication of the present method, may be optimized to result in aplanned center of mass of the total flying system (flight vehicle 200and user or load), depending on the configuration or type of the flightvehicle 200, its mission, and the specific pilot 214 or load 216 placedon the non-fixed portion 210.

The present invention may implement additional stabilization processeswhere necessary. One such process is commonly referred to as aproportional-integral-derivative control method, and this may beutilized by applying certain weights as described below, in the mannerof a potentially nonlinear weighted sum to allow for overall control,the type (responsiveness/agility) of control desired in a givensituation, and for stability.

Stability may therefore be analyzed according to the following equation:

F _(total) =j*F _(present invention) +k*F _(additional.method)

where k and j are weighting factors that may relate to the degree ofperturbation of the non-fixed portion in a non-linear or linear manner,and may be determined using the change, rate of change and rate of rateof change of the degree of perturbation.

After a directional adjustment is calculated from one or both of tiltingor rotating the non-fixed portion 210, the total sum of the propulsionforces acting on the flight vehicle 200 after the directional adjustmentmust be changed in order to maintain constant elevation. This is due tosome of the propulsion force having been transferred intolateral-directional force. The change in overall propulsion force may bedescribed as proportional, in some manner, to the degree of tilt, andmay be determined using the degree of perturbation of the non-fixedportion in a non-linear or linear manner. It may also be determinedusing the change, rate of change and rate of rate of change of thedegree of perturbation, and may further be based on additional factors.The new force may also consider other factors related to the angle ofboth the non-fixed portion 210 and the fixed portion 220 relative to afurther outside frame, the gravitational direction, or the ground.

When adjusted from the two-dimensional case to the three-dimensionalcase, the angle θ is replaced with q) where it is the angle between theplane of the non-fixed portion 210 and the plane of the fixed portion220 of the flight vehicle 200.

A pilot or rider 214 may, in addition to manipulation of the directionof the flight vehicle 200 by movement of the body on the non-fixedportion 210, control flight characteristics such as direction, speed andaltitude in other ways. For example, the pilot or rider 214 may engagelevers or wheels to impart mechanical change on the flight vehicle 200,such as for example to manipulate a rudder or airplane wing flap toalter some flight characteristic. A pilot or rider 214 may also utilizehandheld devices, wireless or otherwise, configured with buttons orlevers, to communicate signals to the flight vehicle 200. It is to beunderstood that many ways of communicating changes or instructionsregarding flight characteristics are possible, and that these may beimplemented and utilized in addition to the tilting and rotation of thenon-fixed portion 210.

In addition to effecting directional changes, tilt and rotation of thenon-fixed portion may also be used to effect changes in the speed andaltitude of the flight vehicle. For example, the present invention maybe configured to recognize that tilting the non-fixed portion 210 mayincrease or decrease the speed of the flight vehicle 200 in a horizontaldirection. In such an example, the more the non-fixed portion 210 istilted a certain direction, the faster it may be propelled. Conversely,a tilt in the opposing direction may cause propulsion to be adjusted soas to slow the flight vehicle 200.

The basis for this is that the thrusters are facing straight down beforetilting, so that all of the force from the thrusters is keeping theflight vehicle 200 at one position. After tilting of the non-fixedportion 210, and the fixed portion 220 tilts to re-orient with thenon-fixed portion 210, the new direction of the thrusters is notvertically down, but at an angle. If the propulsive thrust remained thesame, the flight vehicle 200 would lose altitude, as not all of theforce from the thrusters would be in the vertical, Y-axis direction.However, because the thrusters are themselves tilted following are-orientation, a portion of that thrust would be in the horizontal,X-axis direction. The thrust of the engines must then increase when theflight vehicle 200 tilts, in order for the vehicle to maintain constantaltitude.

The present invention further contemplates that in another embodiment ofthe present invention, the altitude of the flight vehicle 200 may beadjusted by movement of the bod of the pilot 214, such that no handheldcontrol is needed. Further, specific body movements may signal specificinstructions to the flight vehicle 200. In one example of body movementto effect an altitude change, a unique tap, or set of taps, by one orboth feet of the pilot may generate a signal to adjust altitude, begin apre-programmed navigational sequences, or a instruct a command such as“return to launch site.” Also, a unique timing between such taps, orduration of pressure or non-pressure of taps during a tap or tapsequence, may also provide certain instructions to the flight vehicle200. In a further example, a rapid or quick “jolt” on a part (back,front, etc.) of the non-fixed portion 210, followed by a subsequentrapid or quick jolt on another part of the non-fixed portion 210 mayprovide a signal that the pilot or rider intends to increase or decreasealtitude. In such an example, the amount of the increase in altitude maybe configured as a function of the timing and spacing of the locationsof these rapid or quick jolts. It is contemplated that many examples ofthe use of specific body movement are possible and may be implemented inthe present, and the flight vehicle 200 and the flight vehicle controland stabilization process 100 may be configured in many different waysto recognize such specific body movements.

The systems and methods of the present invention may be implemented inmany different computing environments. For example, they may beimplemented in conjunction with a special purpose computer, a programmedmicroprocessor or microcontroller and peripheral integrated circuitelement(s), an ASIC or other integrated circuit, a digital signalprocessor, electronic or logic circuitry such as discrete elementcircuit, a programmable logic device or gate array such as a PLD, PLA,FPGA, PAL, and any comparable means. In general, any means ofimplementing the methodology illustrated herein can be used to implementthe various aspects of the present invention. Exemplary hardware thatcan be used for the present invention includes computers, handhelddevices, telephones (e.g., cellular, Internet enabled, digital, analog,hybrids, and others), and other such hardware. Some of these devicesinclude processors (e.g., a single or multiple microprocessors), memory,nonvolatile storage, input devices, and output devices. Furthermore,alternative software implementations including, but not limited to,distributed processing, parallel processing, or virtual machineprocessing can also be configured to perform the methods describedherein.

The systems and methods of the present invention may also be partiallyimplemented in software that can be stored on a storage medium,non-transitory or otherwise, executed on programmed general-purposecomputer with the cooperation of a controller and memory, a specialpurpose computer, a microprocessor, or the like. In these instances, thesystems and methods of this invention can be implemented as a programembedded on personal computer such as an applet, JAVA® or CGI script, asa resource residing on a server or computer workstation, as a routineembedded in a dedicated measurement system, system component, or thelike. The system can also be implemented by physically incorporating thesystem and/or method into a software and/or hardware system.

Additionally, the data processing functions disclosed herein may beperformed by one or more program instructions stored in or executed bysuch memory, and further may be performed by one or more modulesconfigured to carry out those program instructions. Modules are intendedto refer to any known or later developed hardware, software, firmware,artificial intelligence, fuzzy logic, expert system or combination ofhardware and software that is capable of performing the data processingfunctionality described herein.

The foregoing descriptions of embodiments of the present invention havebeen presented for the purposes of illustration and description. It isnot intended to be exhaustive or to limit the invention to the preciseforms disclosed. Accordingly, many alterations, modifications andvariations are possible in light of the above teachings, may be made bythose having ordinary skill in the art without departing from the spiritand scope of the invention. It is therefore intended that the scope ofthe invention be limited not by this detailed description. For example,notwithstanding the fact that the elements of a claim are set forthbelow in a certain combination, it must be expressly understood that theinvention includes other combinations of fewer, more or differentelements, which are disclosed in above even when not initially claimedin such combinations. It is to be understood that many differentmathematical equations, functions, manipulations, and models may be usedto accomplish the underlying premise that the fixed portion 220 isre-oriented relative to the non-fixed portion 210 of the flight vehicle200 after a perturbation in the planar position of the non-fixed portionfrom one or both of tilt and rotation thereof.

The words used in this specification to describe the invention and itsvarious embodiments are to be understood not only in the sense of theircommonly defined meanings, but to include by special definition in thisspecification structure, material or acts beyond the scope of thecommonly defined meanings. Thus if an element can be understood in thecontext of this specification as including more than one meaning, thenits use in a claim must be understood as being generic to all possiblemeanings supported by the specification and by the word itself.

The definitions of the words or elements of the following claims are,therefore, defined in this specification to include not only thecombination of elements which are literally set forth, but allequivalent structure, material or acts for performing substantially thesame function in substantially the same way to obtain substantially thesame result. In this sense it is therefore contemplated that anequivalent substitution of two or more elements may be made for any oneof the elements in the claims below or that a single element may besubstituted for two or more elements in a claim. Although elements maybe described above as acting in certain combinations and even initiallyclaimed as such, it is to be expressly understood that one or moreelements from a claimed combination can in some cases be excised fromthe combination and that the claimed combination may be directed to asub-combination or variation of a sub-combination.

Insubstantial changes from the claimed subject matter as viewed by aperson with ordinary skill in the art, now known or later devised, areexpressly contemplated as being equivalently within the scope of theclaims. Therefore, obvious substitutions now or later known to one withordinary skill in the art are defined to be within the scope of thedefined elements.

The claims are thus to be understood to include what is specificallyillustrated and described above, what is conceptually equivalent, whatcan be obviously substituted and also what essentially incorporates theessential idea of the invention.

1. A method of control and stabilization of a flight vehicle having atleast one fixed portion and a non-fixed portion; comprising: detecting achange in a position of a non-fixed portion of a flight vehicle relativeto a fixed portion of the flight vehicle, including change resultingfrom at least one of a tilt in planar orientation of the non-fixedportion in any direction and rotation of the non-fixed portion about anaxis perpendicular to the non-fixed portion, wherein the change inposition results in movement of the fixed portion from tilt in planarorientation or rotation about an axis perpendicular to the fixed portionin a direction of re-orientation with the non-fixed portion in responseto the change in relative position between the non-fixed portion and afixed portion, the movement of the fixed portion reducing the relativechange in position between the non-fixed portion and a fixed portion,the resulting planar orientation of a fixed portion closer to the planarorientation of the non-fixed portion after the movement of a fixedportion, the resulting rotation of a fixed portion in the same directionas the non-fixed portion from the movement of a fixed portion, andwherein the non-fixed portion of the flight vehicle is able to tilt orrotate relative to the fixed portion, the fixed portion having at leastone force-generating device from lift, propulsion, or thrust.